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Abstract: In this study, we used oxides (Y2O3, CeO2 and Al2O3) as the raw materials to fabricate YAG:Ce3+ phosphors by a molten salt synthesis (MSS) method. The formation of YAG phase strongly depends on the alumina source and firing temperature. Microstructure characterization indicates that “dissolution-precipitation” mechanism dominates the formation process of YAG in the alkali chlorides melt. Thus, highly active nano-Al2O3 starting powders promote their solution in the melt and guarantee a solute stoichiometric of YAG phase rather than other Y–Al–O compounds. The as-prepared YAG:Ce3+ phosphors show typical yellow emission peaked at 535nm under excitation of 460nm blue light, suggesting that MSS could be a promising method for the preparation of phosphor powders even though oxide raw materials are used. [Copyright &y& Elsevier]

Abstract: Ce3+-doped β-SiAlON blue phosphors with composition of Ce x Si6−z Al z O z N8−z (0.2≤z≤4) at a fixed x=0.01 were synthesized by the gas pressure sintering method. The phases and photoluminescence properties were found to be directly correlated to the z value. Higher z value would result in the formation of AlN polytypoid impurity phases. The optimal z value resides in the range 0.3≤z≤0.5, by which high purity of β-SiAlON phase, good crystallinity and fine grain size were obtained, leading to the best luminescence properties. These phosphors could be a good candidate for application in white light-emitting diodes using InGaN-based near–ultraviolet chips. [Copyright &y& Elsevier]